Formatted question description: https://leetcode.ca/all/1732.html

# 1732. Find the Highest Altitude

Easy

## Description

There is a biker going on a road trip. The road trip consists of n + 1 points at different altitudes. The biker starts his trip on point 0 with altitude equal 0.

You are given an integer array gain of length n where gain[i] is the net gain in altitude between points i and i + 1 for all (0 <= i < n). Return the highest altitude of a point.

Example 1:

Input: gain = [-5,1,5,0,-7]

Output: 1

Explanation: The altitudes are [0,-5,-4,1,1,-6]. The highest is 1.

Example 2:

Input: gain = [-4,-3,-2,-1,4,3,2]

Output: 0

Explanation: The altitudes are [0,-4,-7,-9,-10,-6,-3,-1]. The highest is 0.

Constraints:

• n == gain.length
• 1 <= n <= 100
• -100 <= gain[i] <= 100

## Solution

Start from altitude 0 and calculate altitudes at all indices. Maintain the highest altitude during the process. Finally, return the highest altitude.

• class Solution {
public int largestAltitude(int[] gain) {
int maxAltitude = 0;
int altitude = 0;
int length = gain.length;
for (int i = 0; i < length; i++) {
altitude += gain[i];
maxAltitude = Math.max(maxAltitude, altitude);
}
return maxAltitude;
}
}

• // OJ: https://leetcode.com/problems/find-the-highest-altitude/
// Time: O(N)
// Space: O(1)
class Solution {
public:
int largestAltitude(vector<int>& A) {
int h = 0, ans = 0;
for (int n : A) ans = max(ans, h += n);
return ans;
}
};

• # 1732. Find the Highest Altitude
# https://leetcode.com/problems/find-the-highest-altitude/

class Solution:
def largestAltitude(self, gain: List[int]):
res = [0]
for g in gain:
res.append(res[-1] + g)

return max(res)